He secured the services of Andy Davies, now the company’s chief executive, having previously worked together at fintech start-up CloudMargin, which Mr Davies launched in Silicon Roundabout in London in 2014.

He sold it to venture capitalists and it is now worth more than $10 million.

The pair’s latest enterprise uses an iBeacon, a piece of hardware created by Swatch Group, which transmits a signal several times a second.

This is placed in a wristband or lanyard worn by pupils and tells a teacher’s iPad or mobile phone where they are.